Yes, the "show" parameter is used to ensure you're on the right page of answers, if a question has many answers over multiple pages. So we do ?show=xx where xx is the ID of the answer, then it calculates which page the answer is on.
If you never have more than one page of answers it won't make a difference.
However, all question pages should have the "canonical" URL set in <link rel="canonical" ...> so there should not be any problem in Google.